package com.leyou.item.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.leyou.common.dto.PageDTO;
import com.leyou.common.exception.LyException;
import com.leyou.item.dto.SkuDTO;
import com.leyou.item.dto.SpuDTO;
import com.leyou.item.dto.SpuDetailDTO;
import com.leyou.item.entity.*;
import com.leyou.item.mapper.SpuMapper;
import com.leyou.item.service.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;

import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;


@Service
public class SpuServiceImpl extends ServiceImpl<SpuMapper, Spu> implements SpuService {

    @Autowired
    private CategoryService categoryService;

    @Autowired
    private BrandService brandService;

    @Autowired
    private SpuDetailService detailService;

    @Autowired
    private SkuService skuService;

    @Autowired
    private SpecParamService paramService;

    private void handleCategoryAndBrandName(SpuDTO spuDTO) {
        // 根据品牌id查询品牌名称
        Brand brand = brandService.getById(spuDTO.getBrandId());
        if(brand != null) {
            spuDTO.setBrandName(brand.getName());
        }
        // 根据三级分类id查询分类集合
        List<Category> categories = categoryService.listByIds(spuDTO.getCategoryIds());
        if(!CollectionUtils.isEmpty(categories)) {
            // 取出分类的名称，拼接起来
            String names = categories.stream().map(Category::getName).collect(Collectors.joining("/"));
            spuDTO.setCategoryName(names);
        }
    }

    @Override
    public PageDTO<SpuDTO> querySpuByPage(
            Integer page, Integer rows, Boolean saleable, Long categoryId, Long brandId, Long id) {
        // 1.健壮性
        int current = Math.max(page, 1);
        int size = Math.max(rows, 5);

        // 2.准备查询条件， SELECT * FROM tb_spu WHERE saleable = ? AND category_id = ? AND brand_id = ? AND id = ?
        Page<Spu> result = query()
                .eq(saleable != null, "saleable", saleable)
                .eq(categoryId != null, "cid3", categoryId)
                .eq(brandId != null, "brand_id", brandId)
                .eq(id != null, "id", id)
                // 3.准备分页条件 LIMIT ?, ?
                .page(new Page<>(current, size));

        // 4.解析查询结果
        long total = result.getTotal();
        long pages = result.getPages();
        List<Spu> list = result.getRecords();

        // 5.转换DTO
        List<SpuDTO> dtoList = SpuDTO.convertEntityList(list);
        for (SpuDTO spuDTO : dtoList) {
            // 查询spu的分类和品牌的名称
            handleCategoryAndBrandName(spuDTO);
        }

        // 6.封装分页结果并返回
        return new PageDTO<>(total, pages, dtoList);
    }
    @Transactional
    @Override
    public void saveGoods(SpuDTO spuDTO) {
        // 1.新增Spu
        Spu spu = spuDTO.toEntity(Spu.class);
        spu.setSaleable(false);
        boolean success = save(spu);
        if (!success) {
            throw new LyException(500, "新增商品失败");
        }
        // 2.新增SpuDetail
        SpuDetail spuDetail = spuDTO.getSpuDetail().toEntity(SpuDetail.class);
        spuDetail.setSpuId(spu.getId());
        success = detailService.save(spuDetail);
        if (!success) {
            throw new LyException(500, "新增商品详情失败");
        }
        // 3.新增Sku
        List<Sku> list = spuDTO.getSkus().stream().map(skuDTO -> {
            Sku sku = skuDTO.toEntity(Sku.class);
            sku.setSaleable(false);
            sku.setSpuId(spu.getId());
            return sku;
        }).collect(Collectors.toList());
        // 批量新增
        skuService.saveBatch(list);
    }
    @Override
    @Transactional
    public void updateSaleable(Long id, Boolean saleable) {
        // 1.更新SPU
        Spu spu = new Spu();
        spu.setId(id);
        spu.setSaleable(saleable);
        boolean success = updateById(spu);
        if (!success) {
            throw new LyException(500, "更新失败");
        }
        // 2.更新sku
        success =skuService.update().eq("spu_id", id).set("saleable", saleable).update();
        if (!success) {
            throw new LyException(500, "更新失败");
        }
    }
    @Override
    public SpuDTO queryGoodsById(Long id) {
        // 1.查询spu
        // 1.1.查询
        Spu spu = getById(id);
        if (spu == null) {
            throw new LyException(400, "商品id不存在！");
        }
        // 1.2.转换DTO
        SpuDTO spuDTO = new SpuDTO(spu);

        // 2.查询spuDetail
        SpuDetail detail = detailService.getById(id);
        if (detail == null) {
            throw new LyException(400, "商品id不存在！");
        }
        spuDTO.setSpuDetail(new SpuDetailDTO(detail));

        // 3.查询sku
        List<Sku> list = skuService.query().eq("spu_id", id).list();
        if(CollectionUtils.isEmpty(list)){
            throw new LyException(400, "商品id不存在！");
        }
        spuDTO.setSkus(SkuDTO.convertEntityList(list));

        // 4.准备商品分类和品牌名称
        handleCategoryAndBrandName(spuDTO);

        return spuDTO;
    }
    @Override
    @Transactional
    public void updateGoods(SpuDTO spuDTO) {
        // 1.修改spu
        // 1.1.判断是否存在spu的id，有说明需要修改，没有说明不需要
        Long spuId = spuDTO.getId();
        if(spuId != null){
            // 1.2.spu需要修改，更新spu, 转换dto
            Spu spu = spuDTO.toEntity(Spu.class);
            // 1.3.更新
            boolean success = updateById(spu);
            if(!success){
                // 更新失败，抛出异常
                throw new LyException(500, "更新商品失败！");
            }
        }
        // 2.修改spuDetail
        SpuDetailDTO detailDTO = spuDTO.getSpuDetail();
        // 2.1.判断是否为null
        if (detailDTO != null && detailDTO.getSpuId() != null) {
            // 2.2.spuDetail存在，需要修改，转换DTO
            SpuDetail detail = detailDTO.toEntity(SpuDetail.class);
            boolean success = detailService.updateById(detail);
            if(!success){
                // 更新失败，抛出异常
                throw new LyException(500, "更新商品失败！");
            }
        }
        // 3.修改sku
        List<SkuDTO> dtoList = spuDTO.getSkus();
        // 3.1.判断是否包含sku
        if(CollectionUtils.isEmpty(dtoList)){
            return;
        }
        // 3.2.转换DTO，并将sku根据saleable是否为null来分组。null，是新增或修改，不是null是删除
        Map<Boolean, List<Sku>> map = dtoList.stream()
                .map(skuDTO -> skuDTO.toEntity(Sku.class))
                .collect(Collectors.groupingBy(sku -> sku.getSaleable() == null));

        // 3.3.获取要新增或修改的sku
        List<Sku> insertOrUpdateList = map.get(true);
        // 如果不为空，则修改或新增
        if(!CollectionUtils.isEmpty(insertOrUpdateList)) {
            skuService.saveOrUpdateBatch(insertOrUpdateList);
        }

        // 3.4.获取要删除的sku
        List<Sku> deleteSkuList = map.get(false);
        if(!CollectionUtils.isEmpty(deleteSkuList)){
            // 存在要删除的sku
            List<Long> idList = deleteSkuList.stream().map(Sku::getId).collect(Collectors.toList());
            // 删除
            skuService.removeByIds(idList);
        }
    }
}
